Method and device for service time division multiplexing

ABSTRACT

A method and device for transmitting a multimedia broadcast multicast service are disclosed. A base station sends to a user equipment device position information of specific radio frames in a time unit, and position information of a specific subframe in each of the specific radio frames in the time unit. The time unit includes 2 M  radio frames, and the specific radio frames are two or more of the 2 M  radio frames comprised in the time unit, where M is a nonnegative integer. The base station sends the multimedia broadcast multicast service carried in the specific subframe.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/480,579, filed on Sep. 8, 2014, now U.S. Pat. No. 9,554,382. The U.S.patent application Ser. No. 14/480,579 is a continuation of U.S. patentapplication Ser. No. 13/404,956, filed on Feb. 24, 2012, now U.S. Pat.No. 8,837,455. The U.S. patent application Ser. No. 13/404,956 is acontinuation of U.S. patent application Ser. No. 12/538,357, filed onAug. 10, 2009, now U.S. Pat. No. 8,149,814. The U.S. patent applicationSer. No. 12/538,357 is a continuation of International PatentApplication No. PCT/CN2008/070291, filed on Feb. 5, 2008. TheInternational Patent Application No. PCT/CN2008/070291 claims priorityto Chinese Patent Application No. 200710084514.X, filed on Feb. 12,2007. The afore-mentioned patent applications are hereby incorporated byreference in their entireties.

TECHNICAL FIELD

Embodiments of the present application relates to the communicationtechnical field, in particular to a method and device for service timedivision multiplexing.

BACKGROUND

The third generation partnership projects (3GPP) initiated a long termevolution (LTE) of the 3rd generation (3G) in 2005, and better supportfor increasing service requirements of operators and users is providedthrough evolved universal terrestrial radio access (E-UTRA) and anevolved universal terrestrial radio access network (E-UTRAN).

In an LTE system, downlink communication services can be divided intotwo categories, a unicast service and a multimedia broadcast multicastservice (MBMS). The unicast service refers to a point-to-point servicein which one data source sends data to one user equipment, and the MBMSrefers to a point-to-multipoint service in which one data source sendsdata to multiple user equipment. The introduction of the MBMS is torealize resource sharing on a network. The network, which includes acore network and a radio access network, serves maximum multimedia userequipment having the same requirements by using minimum resources. Inthe radio access network, the MBMS can realize the multicast andbroadcast of messages with plain text at a low rate, and realize themulticast and broadcast of multimedia services at a higher rate on acommon transport channel and a common radio bearer.

For the MBMS, the specification 25.814 of the 3GPP supports two celltransmission modes, one is a multi-cell transmission mode, in whichmultiple cells simultaneously send the MBMS with the same frequencyresource, and the other is a single-cell transmission mode, in which asingle cell sends the MBMS without considering the transmission of othercells.

Data transmission modes of the MBMS include two modes, one is a mixedcarrier (MC) mode, in which the MBMS and the unicast service share thesame carrier to transmit data, and the other is a dedicated carrier (DC)mode, in which the MBMS itself uses one carrier to transmit data. In thecase of the MC mode, it is decided at a 3GPP meeting that the MBMS andthe unicast service are in time division multiplexing, and the twoservices are subframe-level time division multiplexing, i.e., eachservice occupies at least one subframe. If a base station does not senda signaling to inform the usage of each subframe, unicast service userequipment and MBMS user equipment will attempt to read their own serviceinformation through all the transmission time, thus wasting electricenergy of the user equipment. If one bit of information is set for eachsubframe to indicate the usage, for example, one bit has two states, 0and 1, corresponding to the two services respectively, then the requiredinformation amount is very large.

In addition, an orthogonal frequency division multiplexing (OFDM)technology is employed in the downlink of LTE. The OFDM technologydivides a given channel into multiple orthogonal subchannels in afrequency domain, and allows subcarrier spectra to be partiallyoverlapped. As long as mutual orthogonality is met among thesubcarriers, data signals can be obtained. In the operation of an OFDMsystem, symbols are firstly subject to serial/parallel conversion toform multiple low-rate sub-data streams. Each data stream occupies onesubcarrier, the mapping from the sub-data streams to the subcarriers canbe achieved through an inverse discrete Fourier transform (IDFT) or aninverse fast Fourier transform (IFFT). A cyclic prefix (CP) as a guardinterval is applied, which greatly reduces or even eliminatesinter-symbol interference, and ensures orthogonality among variouschannels, thus greatly reducing inter-channel interference.

In the subframe which sends the unicast service or a single-celltransmission MBMS, the length of the CP only needs to meet therequirements of the serving cell. In the subframe of a multi-celltransmission MBMS, however, signal needs to pass through a longertransmission path, in which case a longer CP is required to overcomeinter-symbol interference, and user equipment can successfullydemodulate a subframe only after knowing the length of the CP of thesubframe.

To sum up, the base station in the prior art cannot effectively informthe transmission time of various services and the length of the CP ofeach subframe in the case of time division multiplexing for multipleservices.

SUMMARY

Various embodiments of the present invention provide various objectsincluding a method and device for service time division multiplexing, amethod and a device for transmitting service, and a base station. Theproblem that a base station cannot effectively inform the transmissiontime of various services and the length of the CP of each subframe inthe case of time division multiplexing for multiple services iseffectively overcome.

A method for service time division multiplexing provided by embodimentsof the invention includes: selecting a part or all of radio frames inone time unit as specific radio frames; and selecting a part or all ofsubframes in the specific radio frames as specific subframes for sendinga specific service.

The specific service may be a multimedia broadcast multicast service(MBMS), or a unicast service, or one or more than one kinds of servicestransmitted in broadcast or multicast mode.

A method for transmitting service provided by embodiments of theinvention includes: dividing one time unit into at least one Type 1subunit and selecting a part or all of Type 1 subunits as specific Type1 subunits; dividing each Type n subunit into at least one Type n+1subunit, where 1≦n≦N, and n and N are natural numbers; selecting a partor all of Type n+1 subunits in specific Type n subunits as specific Typen+1 subunits, the specific Type N subunits being used for sending aspecific service; sending the service according to the above timedivision multiplexing mode; and sending position information of the Ntypes of specific subunits.

A method for transmitting service provided by embodiments of theinvention includes: selecting a part or all of the radio frames in onetime unit as specific radio frames; selecting a part or all of subframesin the specific radio frames as specific subframes for sending aspecific service; sending the service according to the above timedivision multiplexing mode; and sending position information of thespecific radio frames and/or position information of the specificsubframes.

The time unit may include several radio frames, each of which contains Rsubframes that can be allocated to the specific service, where R is anatural number.

A device for service time division multiplexing provided by embodimentsof the invention includes: a radio frame selection unit, configured toselect a part or all of radio frames in one time unit as specific radioframes; and a subframe selection unit, configured to select a part orall of subframes in the specific radio frames as specific subframes forsending a specific service.

A device for transmitting service provided by embodiments of theinvention includes: a time division multiplexing unit, configured toselect a part or all of radio frames in one time unit as specific radioframes; and select a part or all of subframes in the specific radioframes as specific subframes for sending a specific service; and atransmission unit, configured to send the service according to a timedivision multiplexing mode determined by the above time divisionmultiplexing unit and send position information of the specific radioframes and/or position information of the specific subframes.

A base station provided by embodiments of the invention includes: adevice for transmitting service, configured to select a part or all ofradio frames in one time unit as specific radio frames, select a part orall of subframes in the specific radio frames as specific subframes forsending a specific service, send the service according to the above timedivision multiplexing mode, and send position information of thespecific radio frames and/or position information of the specificsubframes.

The embodiments of the present invention provide a service time divisionmultiplexing mode. In a technical proposal, a part or all of radioframes in one time unit are selected as specific radio frames, and apart or all of the subframes in the specific radio frames are selectedas specific subframes for sending a specific service. The specificservice may be a multimedia broadcast multicast service, a unicastservice, or one or more than one kinds of services transmitted in themultimedia broadcast multicast mode. Furthermore, in the technicalproposal, services are sent according to the time division multiplexingmode, the position information of the specific radio frames and/or theposition information of the specific subframes are also sent, the timeunit includes several radio frames, and the radio frames includes one ormore subframes that may be allocated to the specific service. It isachieved that when the base station sends multiple services to userequipment through the time division multiplexing mode, the userequipment for various services can accurately obtain the transmissiontime of the services required by the user equipment itself, thusobtaining service data required by the user equipment itself, therebysaving electric energy of the user equipment. Meanwhile, the presentinvention realizes that the user equipment can accurately know thelength of the CP of each subframe by sending length information of theCPs of the specific subframes in the time unit, thus exactlydemodulating the subframes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow diagram of a method for service time divisionmultiplexing of the present invention;

FIG. 2 is a flow diagram of a method for transmitting service of thepresent invention;

FIG. 3 is a flow diagram of an embodiment of a method for transmittingservice of the present invention;

FIG. 4 is a schematic diagram of a multiplexing mode of specificsubframes and nonspecific subframes in an embodiment of a method fortransmitting service of the present invention;

FIG. 5 is a schematic diagram of transmission delay between informationand service data in an embodiment of a method for transmitting serviceof the present invention;

FIG. 6 is a flow diagram of a method for transmitting service accordingto an embodiment of the present invention;

FIG. 7 is a flow diagram of a method for transmitting service accordingto an embodiment of the present invention;

FIG. 8 is a flow diagram of a method for transmitting service accordingto an embodiment of the present invention;

FIG. 9 is a flow diagram of a method for transmitting service accordingto an embodiment of the present invention;

FIG. 10 is a simplified block diagram of a device for service timedivision multiplexing according to an embodiment of the presentinvention;

FIG. 11-A is a simplified block diagram of a device for transmittingservice according to an embodiment of the present invention;

FIG. 11-B is a simplified block diagram of a device for transmittingservice according to an embodiment of the present invention;

FIG. 12-A is a simplified block diagram of a transmission unit in anembodiment of a device for transmitting service of the presentinvention;

FIG. 12-B is a simplified block diagram of a transmission unit in anembodiment a device for transmitting service of the present invention;and

FIG. 13 is a simplified block diagram of a base station according to anembodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

In the case of multi-service time division multiplexing, in order toallow user equipment to know that a subframe is used by which service,embodiments of the present invention provide a service time divisionmultiplexing method and device, as well as a method and a device fortransmitting service.

One time unit is divided into at least one Type 1 subunit, and a part orall of the Type 1 subunits are selected as specific Type 1 subunits.Each of Type n subunits is divided into at least one Type n+1 subunits,where 1≦n≦N, and n and N are natural numbers. A part or all of the Typen+1 subunits in the specific Type n subunits are selected as specificType n+1 subunits, and the Type N subunits are used for sending aspecific service. The service is sent according to the above timedivision multiplexing mode. Position information of N kinds of thespecific Type n subunits is sent. In the embodiments of the presentinvention, the service is multiplexed in the way of dividing one timeunit into N layers by dividing one time unit into Type 1 subunits,dividing each of the Type 1 subunits into Type 2 subunits, and dividingeach of the Type 2 subunits into Type 3 sub-time units and so on.

Referring to FIG. 1, in an embodiment, one time unit is divided into twolayers. A method for service time division multiplexing includes thefollowing steps:

In step S101, a part or all of radio frames in one time unit areselected as specific radio frames.

The size of the time unit can be changed, which means that the number ofthe radio frames included in the time unit may be changed.

In step S102, a part or all of subframes in the specific radio framesare selected as specific subframes for sending a specific service.

The specific service is a multimedia broadcast multicast service, or aunicast service, or one or more than one services transmitted inbroadcast or multicast mode. Particularly, when the specific service isthe multimedia broadcast multicast service or the unicast service, thepresent invention is to solve the problems in the prior art.

The allocation of the specific radio frames in the time unit can bepredefined according to characteristics of the specific service. Forexample, both of base stations and user equipment pre-store a mappingtable or mapping rules. Therefore, when the number of the specific radioframes in the time unit is given, the base stations and the userequipment can know which radio frames are specific radio frames bylooking up the mapping table or by calculating according to the mappingrules. For example, the mapping rule may be that the specific radioframes are evenly allocated. In this way, specific positions of theradio frames can be determined if the number or the interval of theradio frames is determined, thus simplifying multiplexing design. Themode, such as explicit signaling, may be employed rather than employingthe predetermined mode.

In order to further simplify the multiplexing design, the allocation ofthe specific subframes may be the same for every specific radio frame.In this way, specific positions of all specific subframes in the timeunit can be determined only by determining the positions of specificsubframes in one specific radio frame. The allocation of the specificsubframes may not be necessarily the same.

Further, the allocation of the specific subframes in the radio framethat the specific subframes belong to may be predefined without need ofnotification. For example, both of the base stations and the userequipment prestore the mapping table or the mapping rules. When numberof the specific subframes in one specific radio frame is given, the basestations and the user equipment can obtain which subframes are specificsubframes by looking up the mapping table or by calculating according tothe mapping rules. For example, the specific subframes may be evenlyallocated, or allocated at an approximately equal interval in the radioframe that the specific subframes belong to.

The specific positions of the specific subframes can be determined onlyby determining the number or the interval of the specific subframes inone specific radio frame. The even allocation and the approximate evenallocation are hereinafter referred to as the even allocation. The modesuch as explicit signaling rather than the predetermined mode, may beemployed.

Referring to FIG. 2, a method for transmitting service of the presentinvention includes the following steps:

In step S201, a part or all of radio frames in one time unit areselected as specific radio frames.

The time unit includes several radio frames, each of the radio framescontains R subframes that may be allocated to the specific service, andR is a natural number.

In step S202, a part or all of subframes in the specific radio framesare selected as specific subframes for sending the specific service.

The specific service may be a multimedia broadcast multicast service, ora unicast service, or one or more than one kinds of services transmittedin broadcast or multicast mode. Particularly, when the specific serviceis the multimedia broadcast multicast service or the unicast service,the present invention is to solve the problems of the prior art.

The allocation of the specific radio frames in the time unit can bepredefined according to the characteristics of the specific service. Forexample, both of base stations and user equipment pre-store a mappingtable or mapping rules, therefore, when number of the specific radioframes in the time unit is given, the base stations and the userequipment can obtain which radio frames are specific radio frames bylooking up the mapping table or by calculating according to the mappingrules. For example, the mapping rules may be that the specific radioframes are evenly allocated. In this way, specific positions of theradio frames can be determined if the number or the interval of theradio frames is determined, thus achieving the purpose of simplifyingmultiplexing design. The mode, such as explicit signaling rather thanthe predetermined mode, may be employed.

In order to further simplify the multiplexing design, the allocationspecific subframes may be the same for every specific radio frame. Inthis way, specific positions of all specific subframes in the time unitcan be determined only by determining the positions of specificsubframes in one specific radio frames.

Further, the allocation of the specific subframes in the radio framethat the specific subframes belong to may be predefined without need ofnotification. For example, both of the base stations and the userequipment prestore the mapping table or the mapping rules. When numberof the specific subframes in one specific radio frame is given, the basestations and the user equipment can obtain which subframes are specificsubframes by looking up the mapping table or by calculating according tothe mapping rules. For example, the specific subframes may be evenlyallocated, or allocated at an approximately equal interval in the radioframe that the specific subframes belong to. The specific positions ofthe specific subframes can be determined only by determining the numberor the interval of the specific subframes in one specific radio frame.The even allocation and the approximate even allocation are hereinafterreferred to as the even allocation. The mode, such as explicit signalingrather than the predetermined mode, may be employed.

In step S203, the service is sent according to the above time divisionmultiplexing mode.

In step S204, the position information of the specific radio framesand/or the position information of the specific subframes are sent.

Preferably, the position information of the specific radio frames is thenumber or the interval of the specific radio frames in the time unit.

Preferably, the position information of the specific subframes is thenumber or the interval of the specific subframes in each of the specificradio frames.

Preferably, the position information of the specific radio frames and/orthe position information of the specific subframes are transmitted onbroadcast channels.

The position information of the specific radio frames is hereinafterreferred to as first information, and the position information of thespecific subframes is hereinafter referred to as second information.

The broadcast channels include a main broadcast channel, a secondarybroadcast channel and a dynamic broadcast channel. The first informationis transmitted on any one of the three broadcast channels, and thesecond information is transmitted on any one of the three broadcastchannels.

Preferably, the second information is transmitted on the main broadcastchannel, and the first information is transmitted on the secondarybroadcast channel or the dynamic broadcast channel.

The broadcast channels are transport channels, the three transportchannels are mapped to one or more physical channels for transmission.For example, the main broadcast channel is mapped to a physical mainbroadcast channel, the dynamic broadcast channel is mapped to a physicalshared data channel, and the secondary broadcast channel is mapped to aphysical secondary broadcast channel or the physical shared datachannel.

Preferably, the method for transmitting service further includes sendinglength information of CPs of the specific subframes in the time unit.

Preferably, the length information of the CPs is transmitted on thebroadcast channel.

Taking MBMS, which is the specific service, and unicast service timedivision multiplexing as an example, if the service in all MBMSsubframes (specific subframes sending the MBMS) is transmitted inmultiple cells, then all the MBMS subframes use long CPs. If the MBMStransmitted in a single cell is sent in unicast subframes, then thefirst information and the second information are also used for informingthe length of the CPs, that is, all MBMS subframes use the long CPs, andall unicast subframes use short CPs.

If the service in the MBMS subframes is possibly transmitted in multiplecells, and is also possibly transmitted in a single cell, then it issupposed that the service in all the MBMS subframes is transmitted inmultiple cells or transmitted in a single cell in the time unit, thenthe method for transmitting service further includes sending the lengthinformation of the CPs of the specific subframes in the time unit, andthe length information is hereinafter referred to as third information.That is, a user can obtain the length of the CP of each subframe in theentire time unit only by increasing one bit of signaling to inform theMBMS subframes of using the long CP or the short CP. For example, theone bit of signaling is set as 0, which represents the long CP, and theone bit of signaling is set as 1, which represents the short CP, viceversa, the one bit of signaling is set as 1, which represents the longCP, and the one bit of information is set as 0, which represents theshort CP.

Embodiment 1

Referring to FIG. 3, a method for transmitting service of the presentinvention includes the following steps:

In step S301, a part or all of radio frames in one time unit areselected as specific radio frames.

In step S302, a part or all of subframes in the specific radio framesare selected as specific subframes for sending a specific service.

In step S303, the service is sent according to the above time divisionmultiplexing mode.

In step S304, position information of the specific radio frames is sentby sending the value of a signaling m, and 0≦m≦M.

S successive radio frames form one time unit, where S=2^(M), and thevalue of M may be 10 or other numerical values.

The specific radio frames are evenly allocated, and 2^(m) is used torepresent the number of the specific radio frames in the time unit orrepresent the interval of various specific radio frames. If 2^(m) isused to represent the number of the specific radio frames in the timeunit, then the interval of various specific radio frames is 2^(M-m),vice versa, if 2^(m) is used to represent the interval of variousspecific radio frames, then the number of the specific radio frames inthe time unit is 2^(M-m), where 0≦m≦M.

In step S305, the position information of the specific subframes is sentby sending the value of a signaling Np, where 0≦Np≦R and Np representsthe number of the specific subframes in the specific radio frame.

Specific subframe does not exist in the entire time unit when Np=0, inthis case, the value of m is not required to be indicated.

R represents that the radio frame includes R subframes that may beallocated to the specific service. One radio frame occupies 10 ms. Whenall subframes can be allocated to the specific service, the value of Ris temporarily determined as 10 in LTE system. When some subframes cannot be used for sending the specific service, for example, when thesubframes in which a synchronization channel (SCH) is located can onlybe used for the unicast subframes, the value of R is the number of othersubframes in one radio frame. For example, when two subframes in oneradio frame have the SCH, the value of R is 8.

In the present embodiment, the allocation of the specific subframes isthe same for every specific radio frame.

It is described how to determine which subframes in one specific radioframe are the specific subframes after knowing the value of Np by takingapproximate even allocation of the specific subframes in the specificradio frame that the specific subframes belong to as an example:

A simple way is as follows:

Subframes with serial number of r are specific subframes, and the valueof r is calculated by using the following formulas:

$s = \left\lceil \frac{10}{N\; p} \right\rceil$${r = {r_{0} + {\left( {i \cdot s} \right){mod}\; 10} + \left\lfloor \frac{i \cdot s}{10} \right\rfloor}},{i = 0},1,\ldots \mspace{14mu},{{N\; p} - 1}$

In the formula, r₀ is the position of a first specific subframe in thespecific radio frame, and is expressed by the serial number of thesubframe. Generally, r₀=0 can be adopted.

When the value of R is not the number of all subframes in one radioframe, after knowing the value of Np, the positions of the specificsubframes can be also determined by the above method, but the serialnumber of the subframes in the formula is the serial number of othersubframes.

FIG. 4 is a schematic diagram of a multiplexing mode of specificsubframes and nonspecific subframes in the present embodiment. Forexample, a notification m=2 represents the interval of specific radioframes is 4 radio frames, and a first radio frame of the time unitincludes specific subframes. A notification Np=4 represents the specificradio frame has 4 specific subframes which are evenly allocated, and thefirst subframe is a specific subframe, that is, r₀=0.

The information sent in the step S304 is the first information, theinformation sent in the step S305 is the second information, and thefirst information and the second information are transmitted onbroadcast channels.

The broadcast channels include a main broadcast channel, a secondarybroadcast channel and a dynamic broadcast channel. The first informationis transmitted on any one of the three broadcast channels, and thesecond information is transmitted on any one of the three broadcastchannels.

Preferably, when the first information and/or the second information istransmitted on the secondary broadcast channel, the secondary broadcastchannel needs to be predefined to be placed on subframe of the long CP,or placed on the subframe of the short CP.

Preferably, when the first information and/or the second information istransmitted on the dynamic broadcast channel, the dynamic broadcastchannel is determined to be placed on the subframe of the long CP, orplaced on the subframe of the short CP.

When the first information and the second information are transmitted onthe main broadcast channel, as bit number accommodated in the mainbroadcast channel is limited and it is generally acknowledged as 40-50bits, all of the position information can not be put on one mainbroadcast channel, then the information is split into multiple parts,each part is transmitted on one main broadcast channel. One mainbroadcast channel appears once in each radio frame. Therefore, theposition information requires time transmission of multiple radioframes, and this time is an information transmission cycle T. FIG. 5 isa schematic diagram of transmission delay between position informationand service data in the present embodiment. The signaling is repeatedlysent in one time unit. In a first transmission cycle of one time unit,the position of specific subframes is informed by the signaling of thelast transmission cycle of the previous time unit, therefore, signalingcontent has a leading time T corresponding to the position of thespecific subframes indicated by the signaling content.

As value range of m is 0≦m≦M, and the value range of Np is 0≦Np≦R, thebit number needed to transmit the position information is log₂(M+1)+log₂ (R+1).

The user equipment determines the positions of the specific radio framesin the time unit according to the value of m, i.e. the number or theinterval of the specific radio frames. The user equipment determines thepositions of the specific subframes according to the value of Np, i.e.the number or the interval of the specific subframes. The user equipmentthen reads the specific service on the subframes which transmit thespecific service, and reads other services on the subframes whichtransmit other services.

Embodiment 2

Referring to FIG. 6, a method for transmitting service of the presentinvention includes the following steps:

In step S601, a part or all of radio frames in one time unit areselected as specific radio frames.

In step S602, a part or all of subframes in the specific radio framesare selected as specific subframes for sending a specific service.

In step S603, the service is sent according to the above time divisionmultiplexing mode.

In step S604, position information of the specific radio frames is sentby sending the value of a signaling m, where 0≦m≦M+1, and m=M+1represents that the entire time unit has no specific subframe.

S successive radio frames form one time unit, S=2^(M), and the value ofM may be 10 or other numerical values.

The specific radio frames are evenly spaced, and 2^(m) is used torepresent the number of the specific radio frames in the time unit orrepresent the interval of various specific radio frames. If 2^(m) isused to represent the number of the specific radio frames in the timeunit, then the interval of various specific radio frames is 2^(m-m),vice versa, if 2^(m) is used to represent the interval of variousspecific radio frames, then the number of the specific radio frames inthe time unit is 2^(M-m), where 0≦m≦M+1. m=M+1 represents that theentire time unit has no specific subframe.

In step S605, the position information of the specific subframes is sentby sending the value of a signaling Np, where 1≦Np≦R, and Np representsthe number of specific subframes in the specific radio frame; and Rrepresents that the radio frame contains R subframes that may beallocated to the specific service.

When m=M+1, the value of Np is not required to be indicated.

In the present embodiment, the allocation of the specific subframes isthe same for every specific radio frame.

After knowing the value of Np, the method for determining the positionof the specific subframes is the same as that of the embodiment one.

The information sent in the step S604 is the first information, theinformation sent in the step S605 is the second information, and thefirst information and the second information are transmitted on thebroadcast channels. The specific transmission mode is the same as thatof the embodiment one.

As value range of m is 0≦m≦M+1, and the value range of Np is 1≦Np≦R, thetotal bit number for transmitting the position information is┌log₂(M+2)+log₂R┐.

Embodiment 3

The method for transmitting service of the present invention includesthe following steps:

In step S701, a part or all of radio frames in one time unit areselected as specific radio frames.

In step S702, a part or all of subframes in the specific radio framesare selected as specific subframes for sending a specific service.

In step S703, the service is sent according to the above time divisionmultiplexing mode.

In step S704, the position information of the specific radio frames andthe position information of the specific subframes are sent by sendingthe value of a joint signaling A.

S successive radio frames form one time unit, where S=2^(M). 2^(m)represents the number of the specific radio frames in the time unit, orrepresents the interval of the specific radio frames. Np represents thenumber of the specific subframes in the specific radio frame. Rrepresents that the radio frame contains R subframes that may beallocated to the specific service.

In order to further save signaling, the position of the specificsubframes can be indicated by adopting a joint signaling indicationmethod, that is, values of m and Np are sent by sending the signaling A.The specific methods are as follows:

$\begin{matrix}{{{{{If}\mspace{14mu} 0} \leq m \leq M},{0 \leq {N\; p} \leq R},{{{and}\mspace{14mu} R} \leq {M + 1}},{then}}{A = \left\{ {\begin{matrix}{0,{{{when}\mspace{14mu} N\; p} = 0}} \\{{{\left( {M + 1} \right)\left( {{N\; p} - 1} \right)} + \left( {m + 1} \right)},{{{when}\mspace{14mu} 0} < {N\; p} \leq R}}\end{matrix};} \right.}} & (1)\end{matrix}$

In the formula, Np=0 represents that the entire time unit has nospecific subframe.

$\begin{matrix}{{{{{If}\mspace{14mu} 0} \leq m \leq M},{0 \leq {N\; p} \leq R},{{{{and}\mspace{14mu} M} + 1} \leq R},{then}}{A = \left\{ {\begin{matrix}{0,{{{when}\mspace{14mu} N\; p} = 0}} \\{{{Rm} + {N\; p}},{{{when}\mspace{14mu} 0} < {N\; p} \leq R}}\end{matrix};} \right.}} & (2)\end{matrix}$

In the formula, Np=0 represents that the entire time unit has nospecific subframe.

$\begin{matrix}{{{{{If}\mspace{14mu} 0} \leq m \leq {M + 1}},{1 \leq {N\; p} \leq R},{{{{and}\mspace{14mu} M} + 1} \leq R},{then}}{A = \left\{ {\begin{matrix}{0,{{{when}\mspace{14mu} m} = {M + 1}}} \\{{{\left( {M + 1} \right)\left( {{N\; p} - 1} \right)} + \left( {m + 1} \right)},{{{when}\mspace{14mu} 0} \leq m < {M + 1}}}\end{matrix};} \right.}} & (3)\end{matrix}$

In the formula, m=M+1 represents that the entire time unit has nospecific subframe.

$\begin{matrix}{{{{{If}\mspace{14mu} 0} \leq m \leq {M + 1}},{1 \leq {N\; p} \leq R},{{{{and}\mspace{14mu} M} + 1} \leq R},{then}}{A = \left\{ {\begin{matrix}{0,{{{when}\mspace{14mu} m} = {M + 1}}} \\{{{Rm} + {N\; p}},{{{when}\mspace{14mu} 0} \leq m < {M + 1}}}\end{matrix};} \right.}} & (4)\end{matrix}$

In the formula, m=M+1 represents that the entire time unit has nospecific subframe.

In the case of R=M+1, any one of the above expression methods can beused.

It is described how to determine the value of m and Np after knowing thevalue of the signaling A:

It is supposed that two integer variables X and Y are given, wherea₁≦X≦a₂, b₁≦Y≦≦b₂ and a₂−a₁≦b₂−b₁.

A function A is obtained from the following formula:

A=(b2−b1+1)(X−a1)+(Y−b1+1)  (5)

Values of X and Y can be solved through the following formulas if thevalue of A is given:

$\begin{matrix}{X = {a_{1} + \left\lfloor \frac{A}{b_{2} - b_{1} + 1} \right\rfloor}} & (6) \\{Y = {A\; {{mod}\left( {{b\; 2} - {b\; 1} + 1} \right)}}} & (7)\end{matrix}$

When the encoding of the signaling A uses the formula (1) or (3), Np=X,m=Y, and the values of Np and m can be obtained through the formulas (6)and (7).

When the encoding of the signaling A uses the formula (2) or (4), m=X,Np=Y, and the values of Np and m can be obtained through the formulas(6) and (7);

It can be seen that when the sent signaling is A, bit number needed totransmit the position information is ┌log₂[(M+1)R+1]┐ which is possiblyless than information amount ┌log₂(M+1)+log₂(R+1)┐ or ┌log₂(M+2)+log₂R┐for respectively sending the signaling m and Np.

For example, when R=10, and M=8, 9, 10, 11, 16, 17, etc., 1 bit can beeasily saved by the joint signaling. For example, when M=1 and 0≦A≦121,A can be expressed by 7 bits while m and Np are respectively expressedby 4 bits. Therefore, 1 bit of information can be saved by adopting thejoint signaling.

In the present embodiment, the specific radio frames are evenlyallocated.

In the present embodiment, the allocation of the specific subframes isthe same for every specific radio frame.

After knowing the value of Np, the method for determining the positionof the specific subframes is the same as that of the embodiment one.

The information sent by the signaling A includes the first informationand the second information which are transmitted on the broadcastchannels. The specific transmission mode is exactly the same as that ofthe embodiment one.

Embodiment 4

Referring to FIG. 8, a method for transmitting service of the presentinvention includes the following steps:

In step S801, a part or all of radio frames in one time unit areselected as specific radio frames.

In step S802, a part or all of subframes in the specific radio framesare selected as specific subframes for sending a specific service.

In step S803, the service is sent according to the above time divisionmultiplexing mode.

In step S804, the position information of the specific radio frames issent by sending the value of a signaling m, where 0≦m≦M+1, and m=M+1represents that the entire time unit has no specific subframe.

S successive radio frames form one time unit, S=2^(M), and the value ofM may be 10 or other numerical values.

The specific radio frames are evenly spaced, and 2^(m) is used torepresent the number of the specific radio frames in the time unit orrepresent the interval of various specific radio frames. If 2^(m) isused to represent the number of the specific radio frames in the timeunit, then the interval of various specific radio frames is 2^(M-m),vice versa, if 2^(m) is used to represent the interval of variousspecific radio frames, then the number of the specific radio frames inthe time unit is 2^(M-m), where 0≦m≦M+1, and m=M+1 represents that theentire time unit has no specific subframe.

In step S805, the position information of the specific subframes is sentby sending the value of a signaling Np, where 0≦Np≦R, and Np representsthe number of the specific subframes in the specific radio frame inwhich the signaling is located; and R represents that the radio framecontains R subframes that may be allocated to the specific service.

In the present embodiment, the allocation of the specific subframes isthe same for every specific radio frame.

The information sent in the step S804 is the first information, theinformation sent in the step S805 is the second information, and thefirst information and the second information are transmitted on thebroadcast channels. The specific transmission mode is the same as thatof the embodiment one.

Preferably, the second information is transmitted on the main broadcastchannel, and the first information is transmitted on the secondarybroadcast channel or the dynamic broadcast channel.

The following paragraphs describe an example that the first informationis transmitted on the secondary broadcast channel and the secondinformation is transmitted on the broadcast channel.

The user equipment receives the main broadcast channel firstly to obtainthe value of Np, thus knowing the length of the CP of each subframe inthe radio frame in which the main broadcast channel is located. If thecurrent radio frame includes the secondary broadcast channel, then theuser equipment can solve the value of m, otherwise, the user equipmentsuccessively receives and checks the main broadcast channel until thesecondary broadcast channel is found, and the value of m is solved.

When Np≠0, the user equipment may obtain the position information of thespecific subframes in the time unit by combining the value of m. WhenNp=0, m=M+1 indicates that the time unit has no specific subframe, andthus the user equipment also obtains the information of the service thateach subframe in the time unit is used for. When Np=0, if m≠M+1, theuser equipment may obtain the position of the radio frame of Np≠0according to the value of m, and reads the value of Np on the mainbroadcast channel in such radio frame, thus obtaining the positioninformation of the specific subframes in the time unit.

It should be noted that Np may indicate the number of the specificsubframes in any one designated radio frame. For example, Np canindicates the number of the specific subframes in the first or severalradio frame next to the radio frame in which Np is located.

The user equipment may obtain the number of the specific subframes inthe designated radio frame after receiving the value of Np. Then theuser equipment may obtain the length of the CP of each subframe in theradio frame. Then, the procedures such as obtaining the value of m,checking whether Np is zero value, etc. by the user equipment areexactly the same as that of the above method. Finally, the userequipment may obtain nonzero values of Np and m, and thus obtain theposition of the specific subframes in the time unit.

Preferably, the length information of the CP are transmitted togetherwith the value of Np on the same channel.

Embodiment 5

Referring to FIG. 9, the method for transmitting service includes thefollowing steps:

In step S901, a part or all of radio frames in one time unit areselected as specific radio frames.

In step S902, a part or all of subframes in the specific radio framesare selected as specific subframes for sending a specific service.

In step S903, the service is sent according to the above time divisionmultiplexing mode.

In step S904, the position information of the specific radio frames issent by sending the value of a signaling F. When the number of thespecific radio frames in the time unit is more, the time unit is dividedinto several sub-time units. F represents the position information ofthe specific radio frames in the sub-time units. And, the positioninformation of the specific radio frames in several sub-time units isthe same. When the number of the specific radio frames in the time unitis less, F represents the position information of the specific radioframes in the time unit.

The present invention may be embodied in many different forms asfollows, but should not be construed as limited to the embodiments setforth herein.

S successive radio frames form one time unit, where S=2^(M) and thevalue of M may be 10 or other numerical values. The time unit is dividedinto 2^(M-M) ⁰ sub-time units, and each sub-time unit consists of 2^(M)⁰ successive radio frames, and M0 is a positive integer smaller than M.

In step S904.1 (not shown), when the number of the specific radio framesin the time unit is more than or equals 2^(M-M) ⁰ , F represents theposition information of the specific radio frames in the sub-time unit.

For example, F may represent a bitmap Fq of the radio frames in thesub-time unit, Fq consists of 2^(M) ⁰ bits, each bit corresponds to oneradio frame, and represents whether the corresponding radio frame isallocated to the specific service or not with two states which are 0 and1.

Another example is that F may represent the number Fp of the radioframes in the sub-time unit, and 0<Fp≦2^(M) ⁰ . The specific radioframes in a same sub-time unit are allocated according to a preset rule,for example, successive allocation or even allocation. If Fp specificradio frames are of approximate even allocation in the sub-time unitthat the specific radio frames belong to, the method for determining theposition of the radio frames is similar to the method for determiningthe specific subframes after knowing the value of Np in the embodimentone. If Fp specific radio frames are consecutively allocated in thesub-time unit that the specific radio frames belong to, then thepositions of the specific radio frames can be determined according to astarting position f₀ of the successive Fp specific radio frames and thevalue of Fp. The starting position f₀ may be appointed or informed bysignaling, particularly, f₀ may be appointed as 0.

In step S904.2 (not shown), when the number of the specific radio framesin the time unit is less than 2^(M-M) ⁰ , F represents the positioninformation of the specific radio frames in the time unit.

Example 1, F can represent a bitmap Gq of the sub-time units in the timeunit, Gq consists of e bits, each bit corresponds to one sub-time unit,and represents whether the corresponding sub-time unit includes onespecific radio frame or not with the two states which are 0 and 1. Thepositions of the specific radio frames are identical in various sub-timeunits that the specific radio frames respectively belong to, and thepositions can be appointed or informed by the signaling.

Example 2, F can represent the number Gp of the specific radio frames inthe time unit, 0≦Gp<2^(M-M) ⁰ 2^(M-M) ⁰ , and the allocation rules ofthe specific radio frames can be appointed or informed by the signaling.The following paragraphs provide three examples of appointed allocationrules.

(1). When Gp specific radio frames are appointed to be consecutivelyallocated in the time unit, the positions of the specific radio framescan be determined according to a starting position g₀ of the successiveGp specific radio frames and the value of Gp. The starting position g₀can be appointed or informed by the signaling, particularly, g₀ may beappointed as 0.

(2). When Gp specific radio frames are appointed to be allocated in Gpsuccessive sub-time units of the time unit, the positions of thesub-time units including the specific radio frames can be determinedaccording to a starting position g′₀ of the Gp successive sub-time unitsand the value of Gp. The starting position g′₀ can be appointed orinformed by the signaling, particularly, g′₀ may be appointed as 0. Thepositions of the specific radio frames are identical in various sub-timeunits that the specific radio frames respectively belong to. Theposition can be appointed or informed by the signaling. Particularly,the position may be a first radio frame in the sub-time unit.

Example 3, F represents the number 2^(m) of the specific radio frames inthe time unit, and in the time unit, the specific radio frames areevenly allocated or consecutively allocated. Or F represents theinterval 2^(m) of the specific radio frames in the time unit, and thespecific radio frames are evenly allocated.

If 2^(m) is used to represent the number of the specific radio frames inthe time unit, where 0≦m≦M−M₀ or 0≦m≦M−M₀, and m=M−M₀ is used toindicate that the entire time unit has no specific subframe, when thespecific radio frames are evenly allocated, the interval is 2^(M-m);vise versa, if 2^(m) is used to represent the interval of variousspecific radio frames, then the number of the specific radio frames inthe time unit is 2^(M-m), where M₀<m≦M or M₀≦m≦M, and m=M₀ is used torepresent that the entire time unit has no specific subframe.

In step S905, the position information of the specific subframes is sentby sending the value of a signaling Np or the value of Nq, where Nprepresents the number of the specific subframes in the specific radioframe and 0≦Np≦R; R represents that the radio frame contains R subframesthat may be allocated to the specific service; and Nq is a bitmap of thesubframes in the specific radio frame. Specifically, Nq consists of Rbits, each bit corresponds to one allocable subframe, and representsthat whether the corresponding subframe is allocated to the specificservice or not with two states which are 0 and 1.

In the present embodiment, the allocation of the specific subframes isthe same for every specific radio frame.

After knowing the value of Np, if Np specific subframes are allocated atapproximate equal interval in the specific radio frame that the specificsubframes belong to, the method for determining positions of thespecific subframes is exactly the same as that of the embodiment one. IfNp specific subframes are consecutively allocated in the specific radioframe that the specific subframes belong to, then the positions of thespecific subframes can be determined according to a starting position r₀of successive Np subframes and the value of Np, and the startingposition r₀ can be appointed or informed by the signaling, particularly,r₀ may be appointed as 0.

The information sent in the step S904 is the first information, theinformation sent in the step S905 is the second information, and thefirst information and the second information are transmitted on thebroadcast channels. The specific transmission mode is the same as thatof the embodiment one.

As value range of m is 0≦m≦M+1, and the value range of Np is 1≦Np≦R, thetotal bit number for transmitting the position information is┌log₂(M+2)+log₂R┐.

The embodiment six is a multilayer embodiment, and specifically is asfollows: when the number of the specific Type N′ subunits in the timeunit is more than or equals a threshold, the value of n₀ is determined,where 1≦N′≦N, 1≦n₀≦N, n₀ has at least one value, which represents thatall of the Type n₀ subunits in the specific Type n₀−1 subunit are thespecific Type n₀ subunits, and the position information of the specificType n₀ subunits is not sent any more. When the number of the specificType N′ subunits in the time unit is less than a threshold, the value ofn₀′ is determined, where 1≦n₀′≦N, n₀′ has at least one value, whichrepresents that the Type n₀′−1 subunit are directly divided into atleast one Type n₀′+1 subunit, and the position information of thespecific Type n₀′ subunits is not sent any more. The Type 0 subunit isthe time unit, and the sizes of the Type n subunits do not change withthe preceding operations.

For example, the time unit is divided into 2^(M-m) ⁰ Type 1 subunits,both M and M₀ are nonnegative integers, and M₀≦M. Each Type 1 subunit isdivided into 2^(M) ⁰ Type 2 subunits, the Type 2 subunits are the radioframes, and Type 3 subunits are the subframes. Each Type 2 subunit isdivided into at least one Type 3 subunit. In addition, the positioninformation of the specific Type n subunits is sent by sending the valueof the signaling F, where n=1 or n=2. When the number of the specificType 2 subunits in the time unit is more than or equals 2^(M-M) ⁰ ,n₀=1, and F represents bitmap and/or number and/or interval of thespecific Type 2 subunits in each Type 1 subunit. When the number of thespecific Type 2 subunits in the time unit is less than 2^(M-M) ⁰ ,n₀′=2, and F represents bitmap and/or number and/or interval of thespecific Type 2 subunits in the time unit. The position information ofthe Type 3 subunits is sent by sending the value of the signaling G,where G represents bitmap and/or number and/or interval of the specificType 3 subunits in the specific Type 2 subunit that the specific Type 3subunits belong to.

The present invention further provides a device corresponding to theservice time division multiplexing method, a device corresponding to themethod for transmitting service and a base station.

The service time division multiplexing device of the present inventionincludes a radio frame selection unit and a subframe selection unit.

The radio frame selection unit is configured to select a part or all ofradio frames in one time unit as specific radio frames.

The subframe selection unit is configured to select a part or all ofsubframes in the specific radio frames as specific subframes for sendinga specific service.

The device for transmitting service of the present invention includes atime division multiplexing unit and a transmission unit.

The time division multiplexing unit is configured to select a part orall of radio frames in one time unit as specific radio frames; andselect a part or all of subframes in the specific radio frames asspecific subframes for sending a specific service.

The transmission unit is configured to transmit the service according toa time division multiplexing mode determined by the time above divisionmultiplexing unit and send position information of the specific radioframes and/or position information of the specific subframes.

The base station of the present invention includes a servicetransmission device.

The service transmission device is configured to select a part or all ofradio frames in one time unit as specific radio frames, select a part orall of subframes in the specific radio frames as specific subframes forsending a specific service, send the service according to the above timedivision multiplexing mode, and send position information of thespecific radio frames and/or position information of the specificsubframes.

The following paragraphs provide several embodiments of the devices ofthe present invention.

Embodiment 7

Referring to FIG. 10, the service time division multiplexing device 91according to one embodiment of the present invention includes a radioframe selection unit 911 and a subframe selection unit 912.

The radio frame selection unit 911 is configured to select a part or allof radio frames in one time unit as specific radio frames.

The subframe selection unit 912 is configured to select a part or all ofsubframes in the specific radio frames as specific subframes for sendinga specific service.

The specific service is a multimedia broadcast multicast service, or aunicast service, or one or more than one kinds of services transmittedin broadcast or multicast mode.

Embodiment 8

Referring to FIG. 11-A, the device for transmitting service 101according to one embodiment of the present invention includes a timedivision multiplexing unit 1011 and a transmission unit 1012.

The time division multiplexing unit 1011 is configured to select a partor all of radio frames in one time unit as specific radio frames andselect a part or all of subframes in the specific radio frames asspecific subframes for sending a specific service.

The specific service is a multimedia broadcast multicast service, or aunicast service, or one or more than one kinds of services transmittedin broadcast or multicast mode.

The transmission unit 1012 is configured to transmit the serviceaccording to a time division multiplexing mode determined by the abovetime division multiplexing unit 1011 and send position information ofthe specific radio frames and/or position information of the specificsubframes.

Preferably, referring to FIG. 11-B, the device for transmitting service101 according to one embodiment of the present invention furtherincludes a position information generation unit 1013.

The position information generation unit 1013 is configured to generatethe position information of the specific radio frames and/or theposition information of the specific subframes according to the specificradio frames and the specific subframes selected by the time divisionmultiplexing unit 1011.

Preferably, referring to FIG. 12-A, the transmission unit 1012 mayinclude a service transmission unit 10121 and a position informationtransmission unit 10122.

The service transmission unit 10121 is configured to transmit theservice according to the time division multiplexing mode determined bythe above time division multiplexing unit 1011.

The position information transmission unit 10122 is configured totransmit the position information of the specific radio frames and/orthe position information of the specific subframes.

Preferably, Referring to FIG. 12-B, the transmission unit 1012 mayfurther include a prefix length transmission unit 10123.

The prefix length transmission unit 10123 is configured to transmitinformation which indicates length of CPs of the specific subframes inthe time unit.

Embodiment 9

Referring to FIG. 13, the base station 121 according to one embodimentof the present invention includes a device for transmitting service1211.

The device for transmitting service 1211 includes a time divisionmultiplexing unit 12111 and a transmission unit 12112.

The device for transmitting service 1211 is configured to select a partor all of radio frames in one time unit as specific radio frames; selecta part or all of subframes in the specific radio frames as specificsubframes for sending a specific service; send the service according tothe above time division multiplexing mode; and send position informationof the specific radio frames and/or position information of the specificsubframes.

The specific service is a multimedia broadcast multicast service, or aunicast service, or one or more than one kinds of services transmittedin broadcast or multicast mode.

The time division multiplexing unit 12111 is configured to select a partor all of radio frames in one time unit as the specific radio frames andselect a part or all of subframes in the specific radio frames as thespecific subframes for sending the specific service.

The transmission unit 12112 is configured to transmit the serviceaccording to the time division multiplexing mode determined by the abovetime division multiplexing unit 12111 and send the position informationof the specific radio frames and/or the position information of thespecific subframes.

To sum up, the present invention provides a service time divisionmultiplexing method and a service time division multiplexing device aswell as a method and a device for transmitting service. Particularly,the present invention provides an MBMS and unicast service time divisionmultiplexing method and a device thereof, as well as a method and adevice for sending the MBMS and the unicast service, which prevents aunicast service user and an MBMS user from reading own serviceinformation in the transmission time of the other side, and saveselectric energy for the user equipment. The method for informing thelength of the CP of the subframe provided by the present inventionensures that the user equipment can exactly demodulate the subframes.The information transmission path, the information timing mode and theinformation source encoding mode provided by the present inventionensure that the user equipment can accurately obtain the transmissiontime of required service data and read the corresponding service datawhen the service data are sent in the case that the base station employsthe MBMS and unicast service time division multiplexing mode, thussaving resources.

The specific service referred in the present invention includes aservice with specific content or a service transmitted through aspecific transmission mode, and also includes the service with thespecific content and transmitted through the specific transmission mode.

The service transmitted through specific mode includes multiple types,for example, a service transmitted through a multimedia broadcastmulticast mode, or a service transmitted through a unicast mode. Thespecific mode can also refer to an antenna configuration mode, a timefrequency resource occupancy mode, a code resource occupancy mode, aspace frequency occupancy mode, etc. The specific mode can also refer toa destination equipment of the service, for example, one or more thanone kind of services transmitted to a certain specific user or aspecific user group.

The service with the specific content includes any one or more than onekinds of multimedia broadcast multicast services, for example, streamingmedia services, data sharing services, etc. The service with thespecific content can also include any one or more than one kinds ofunicast services.

The service with the specific content and transmitted through a certainspecific transmission mode can be inferred from the explanation of thespecific mode and the specific content, for example, a voice servicetransmitted through the unicast mode.

Finally, it should be noted that the above embodiments are merelyprovided for describing the technical solutions of the presentinvention, but not intended to limit the present invention. It should beunderstood by those of ordinary skill in the art that although thepresent invention has been described in detail with reference to theforegoing embodiments, modifications can be made to the technicalsolutions described in the foregoing embodiments, or equivalentreplacements can be made to some technical features in the technicalsolutions, as long as such modifications or replacements do not causethe essence of corresponding technical solutions to depart from thescope of the present invention.

What is claimed is:
 1. A communication method, comprising: sending, by abase station to a user equipment device, position information ofspecific radio frames in a time unit, and position information of aspecific subframe in each of the specific radio frames in the time unit;and sending, by the base station, a multimedia broadcast multicastservice (MBMS) carried in the specific subframe; wherein the time unitcomprises 2^(M) radio frames, and the specific radio frames are two ormore of the 2^(M) radio frames comprised in the time unit, where M is anonnegative integer.
 2. The method of claim 1, wherein the specificradio frames are evenly distributed in the time unit, and every 2^(m)radio frames in the time unit include one specific radio frame, whereinthe position information of the specific radio frames in the time unitis represented by a period of the specific radio frames in the timeunit, and a length of the period is 2^(m) radio frames, where m is aninteger and 0≦m≦M.
 3. The method of claim 1, wherein the method isapplied in a long term evolution (LTE) system.
 4. The method of claim 1,wherein a position of the specific subframe in a specific radio frame isthe same for every specific radio frame.
 5. The method of claim 1,wherein the position information of specific radio frames in the timeunit and the position information of the specific subframe in each ofthe specific radio frames are sent through a physical shared datachannel.
 6. The method of claim 2, wherein the position information ofspecific radio frames in the time unit and the position information ofthe specific subframe in each of the specific radio frames are sentthrough a physical shared data channel.
 7. A base station, comprising: aprocessor, a non-transitory computer readable storage medium storinginstructions for execution by the processor, and a transmitter; whereinthe instructions, when executed by the processor, cause the transmitterto: transmit to a user equipment device, position information ofspecific radio frames in a time unit, and position information of aspecific subframe in each of the specific radio frames in the time unit;and transmit a multimedia broadcast multicast service (MBMS) carried inthe specific subframe; wherein the time unit comprises 2^(M) radioframes, and the specific radio frames are two or more of the 2^(M) radioframes comprised in the time unit, where M is a nonnegative integer. 8.The base station of claim 7, wherein the specific radio frames areevenly distributed in the time unit, and every 2^(m) radio frames in thetime unit include one specific radio frame, wherein the positioninformation of the specific radio frames in the time unit is representedby a period of the specific radio frames in the time unit, and a lengthof the period is 2^(m) radio frames, where m is an integer and 0≦m≦M. 9.The base station of claim 7, wherein the base station is an evolved basestation in a long term evolution (LTE) system.
 10. The base station ofclaim 7, wherein a position of the specific subframe in a specific radioframe is the same for every specific radio frame.
 11. The base stationof claim 7, wherein the position information of specific radio frames inthe time unit and the position information of the specific subframe ineach of the specific radio frames are sent through a physical shareddata channel.
 12. The base station of claim 8, wherein the positioninformation of specific radio frames in the time unit and the positioninformation of the specific subframe in each of the specific radioframes are sent through a physical shared data channel.